


Why...?

by Musehanna99



Category: Undertale (Video Game)
Genre: Daddy kink later on, Don't be angry, F/M, Frisk killed almost everyone before the story start, Sans has more of the underfell Sans's personality than anything, Sans is violent towards OC, barely anyone is alive anymore, rape appears later on, slightly yandere Sans, this helps add to the story, um.. yeah you've been warned.
Language: English
Status: In-Progress
Published: 2016-01-01
Updated: 2015-12-31
Packaged: 2018-05-10 15:10:58
Rating: Explicit
Warnings: Graphic Depictions Of Violence, Rape/Non-Con, Underage
Chapters: 1
Words: 1,618
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5590942
Author URL: https://archiveofourown.org/users/Musehanna99/pseuds/Musehanna99
Summary: <blockquote class="userstuff">
              <p>After Ana Rein falls down into the land of Undertale, things take a turn for the worst for her. Ever since Papyrus and nearly all of Sans's friends were killed by Frisk, Sans hasn't been the same. He still goes to Grillby's every day but he's more quiet than he used to be. Sure he still cracks the occasional bone pun and has his same old smile but there's just something off about it. Grillby and Monster Kid have noticed but, they don't say anything about it. Once Ana arrives Sans becomes extremely quiet to the other remaining monsters in the small anarchy, but when it comes to Ana.. well you could say that Ana is in for a not so pleasant surprise. After gaining her trust after a few months, Ana thinks of him as a father. One day Sans invites her over to his home and she gets knocked out. After that Sans keeps her prisoner in his home and uses her as a sex slave and torture victim to take his anger against humanity out on her.</p>
            </blockquote>





	Why...?

**Author's Note:**

> I'll put little **** whenever smut is about to start. If you're not a fan of smut don't read.

(First up will be a character map)  
Name: Ana Rein  
Age: 15  
Hair color/length: Black/ mid back with fringe over left eye  
Eye color: Left eye-red Right eye-lavender  
Skin color: Pale (nearly snow white)  
Species: Demon/Human hybrid  
Demon type: Shadow  
Abilities: Shadow control (can make weapons and shields), quick healing, faster than a human, has more stamina than a human Height: 4'9"  
Weight: 100 lbs  
Clothing: Black tank top, white hoody, dark jean shorts, black and white striped, and combat boots (link to see: https://plus.google.com/u/0/112078660961026708575/posts/ct1Z7LNRyza?pid=6234641726219651954&oid=112078660961026708575 ) Body type: thin, short, dainty, slight curves, B-cup size breasts, average ass size.  
Personality: Nice, caring, tom-boy, adventurous, normally really calm, and innocent  
Likes: Sweets, music, hugs, singing, drawing  
Dislikes: Mean people, pain, violence, yelling  
Family:  
-Father- Sean Fressich. Black hair, red eyes, pale. Abusive, sadistic. Centuries old. Demon. (deceased)  
-Mother- Rebecca Hollin. Brown hair, left eye- brown right eye- lavender, tan. Kind, loves to laugh, forgiving. 30 years old. Human (deceased)  
-Sister- Frisk Hollin. Brown hair, brown eyes that turn red when her powers are being used, tan skin. Violent, vengeful, quiet. 12 years old. Human/Demon Hybrid, mostly Demon. (deceased)  
~~~~Story Start~~~~  
I walk up Mount Ebott, my breath forming in white puffs of vapor in front of me, and shiver due to the cool mountain air. Why am I going here again?... Oh right... my little sister Frisk disappeared up here half a year ago and I haven't stopped looking for her. After mom died she grew very angry and disappeared up the mountain. Nobody has seen her since then... I'm worried that she might have gotten hurt, but I'm certain I'll find her. She always was a tough kid and could handle a lot of injuries, but her powers weren't stable like mine. She hadn't perfected her control over the shadows yet and while her time control was always rather good, it was also unstable from her young age and the beginnings of puberty hitting her like a freight train.  
I'm so deep in thought that my mind doesn't register that I'm falling until I'm about to hit the bottom and my eyes widen, red eye glowing instinctively as shadows grab onto my arms and legs, stopping my fall just inches from the floor and making me sigh in relief, setting myself down rightside up. I take the chance to form a flame of shadows in my hand, dimly lighting up the cave I find myself in.... I sniff the air, my slightly pointed ears twitching. I smell... Frisk! Its faint but there! Frisk fell here! I smile excitedly and clap my hands, following the scent through the cave and then after two doors, find myself in strange purple rooms and after a while I find strange piles of dust. Wait dust...? I remember father teaching us about monsters and once they die they turn to dust.  
I frown and say softly,"Frisk.. tell me you didn't... Please tell me you didn't..."  
I shake my head sadly and continue on, eventually getting through it all and reaching a snowy forest. I glance around and then realize that I've lost Frisk's scent in the snow and before the door that lead to the forest, the scent was muddled with the scent of slain monsters. I shiver from the cold and continue on, DETERMINATION to find Frisk filling me and making me continue on. I reach a bridge that has strange bars that are too wide to stop anyone built on it and tilt my head.  
I say quietly,"Is is supposed to stop anyone?..."  
I shrug and then continue on, eventually finding a small town that seems abandoned. I glance around and see a light in the diner looking place, so I walk over to it and go inside. I see a man made of fire and for some reason it doesn't surprise me. I walk over to him and he looks up, his head flaring slightly as he takes a few steps back.  
He says in a voice that sounds kind of like a French person,"What are you doing here human?"

I tilt my head and say softly,"I'm looking for my sister Frisk... she went missing half a year ago and I think she may have fallen down here... I have um.. noticed in the ruins what has happened and I have to say that I am sorry for her behavior... She hasn't been the same since mother died and I realize that she has hurt a lot of people... If you could tell me if you've seen her or where she is, that would be great.... I'd love to stop the behavior she's been showing to your kind..."  
The man stares at me in bewilderment and then he chuckles and says,"The sibling of that little murderer has some compassion... I'm surprised..."  
I wince slightly at the word "murderer" and say quietly,"I'm sorry again for the trouble she has been causing.... Can you point me in the direction she was last seen?"  
He sighs and says softly,"Actually she was killed months ago... but only after leaving very little to no survivors in each area of the underground she went to... When she died the human souls that we had gathered disappeared somehow and we were going to keep her's stored to try and save up but.... she wasn't entirely human. Wouldn't happen to know anything about that would you?"  
He seems to be raising an eyebrow at me and I look away hesitantly, feeling a small amount of sadness before saying,"I guess it wouldn't hurt anyone to explain.. our mother was human, but our father was a demon of shadow and time... I gained control over shadows but it seems I didn't inherit the time control that Frisk had... Frisk's time control was more in tuned with her body than the shadow control that I have, making it extremely unstable. There were also multiple occurrences where Frisk's time travel has failed her and she nearly died, which I'm thinking may have happened to help her cause in death."  
Its not that I don't care that she was killed, its more to the fact that it was probably for the best and I have a feeling that I would've had to kill her myself if nobody else had.  
The fire man nods and after a short silence, he says,"So you both are demon-human hybrids?"  
I nod in response to his question and say,"That's correct.. although Frisk has always been rather unstable... I was supposed to be training her but she ran off to here..."  
After a short talk with the man, I learn his name is Grillby and that there are perhaps 15 remaining monsters in the underground. After using the small amount of monster currency I have to buy a burger from him, the door to the tiny diner opens up with a dinging sound and I turn in my seat, seeing a short skeleton wearing a blue hoodie, black basketball shorts, pink slippers and a black shirt. I take notice to the stains of violet on his slippers and take a bite of my burger lazily, knowing immediately that he's the one that stopped my sister. Our father had black blood and Frisk had violet blood. As for me, well my blood is blue.   
As soon as he sees me, he freezes and then walks over, keeping the white glowing pupils in his eye sockets trained on me at all times. I raise an eyebrow and wave, finishing my burger. There's something a bit strange about this food. It disappears as soon as you swallow it and afterwards you can feel emotions that aren't yours. The burger is making me feel uneasy and I think I've read about this somewhere. Monster food is cooked with magic and the emotions the cook is feeling. So Grillby must be feeling uneasy around me? How cute... I don't blame him though, especially after Frisk went through here.  
I look at the skeleton boredly as he sits next to me and I say quietly,"So you're the one that killed my little sister, Frisk, eh?"  
He stiffens noticeably and turns to look at me, his left eye flaring up with a blue flame and I sense his level of power is extremely high, making me smirk, saying,"Interesting... so you're that strong..."  
He glares at me and opens his mouth to say something and I simply cut him off quickly by saying,"Hey... calm down, yeah? I'm not gonna attack you over Frisk... She got what was coming to her. She should've known not to just slaughter innocent souls because she was upset about our mother."  
He freezes and I glance at Grillby before saying while getting up,"Well I'll be on my way Grillby... thanks for the food and... there's no need to feel uneasy around me, ya know..."  
I sense Grillby freeze while polishing a cup and snicker, walking out into the cold town. Unknown to me though, the small skeleton is following me and his intentions are not good.  
*Timeskip*   
Its been a few months since I've been in the underground and Sans has somehow wormed his way into becoming something like a fatherly figure. I don't know how he managed, but honestly I don't mind it. Its nice to have that kind of figure in my life especially after everything that happened with my biological father. Sans invited me over to his house, something he's never done before, and of course I accepted because I trust him. So here I am, on my way there now.


End file.
